Microfluidic optical systems
“From a high level, microfluidic applications are attempting to achieve the same thing as biometric systems,” said David Simpson, vice president of sales and marketing for New Scale. “In a macro sense, applications for DNA analysis, identification, and medical diagnostics for pathogens and other environmental contaminants are being analyzed on very large, expensive laboratory-based systems that require highly trained personal to perform the sample preparation, testing, and analysis.”
The overall design goals are to decrease the size and complexity of the machines, reduce the cost per test to less than $1,000, and decrease the time required in testing. Instrument makers are trying to deliver portable devices that are small enough and cost-effective enough to be deployed in remote field locations, individual doctor offices, and forensic labs.
“The goal is to avoid the need to send these samples back to a central clearing house. But in order to do that, the systems need to develop a process to handle the samples without needing trained scientists, and is affordable. That is where microfluidics chip comes in,” Simpson told us.
Microfluidics technology is enabling a cartridge approach to processing samples, where systems can pre-package the chemistry and achieve efficient handling of the sample. These microfluidics chips are providing the possibility to meet these new design goals.
“However, there are challenges with the microfluidics cartridge. It works well because the cartridge is disposable; it eliminates the problem of how to manipulate the sample, and can be housed in a small instrument box,” said Simpson. “But there are small mechanical variations and tolerances in the cartridges, and the question is how to align the instrumentation with the microfluidics channel. Essentially, the applications are aligning and focusing their optical systems to the microfluidic channels to allow for accurate analysis of the samples.”
Precise micro-motion systems are enabling these new technologies by making the devices smaller, less expensive, and more automated to allow testing to be done by lower level personnel in a faster time frame. Their ability to provide high-resolution micro positioning in a range of travel makes it possible for systems to align the light sources to the channels, and effectively focus the light onto the sensors and detectors. Even though there are variations with the cartridges used, the system has the ability to achieve quick alignment and focusing on the samples to perform the science that is needed.
“Beyond the small, precise, high-resolution motion capabilities required, another aspect of this technology that is driving rapid adoption and enabling customers to commercialize these products is that it is also a smart system,” said Simpson.